


I'd trade all my tomorrows for just one yesterday

by BladedDarkness



Series: SuperHogwarts [1]
Category: Supergirl (TV 2015)
Genre: Alternate Universe - Hogwarts, F/F, Pre-Relationship, Slow Burn
Language: English
Status: Completed
Published: 2016-05-24
Updated: 2016-05-24
Packaged: 2018-06-10 13:16:28
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,322
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6957952
Author URL: https://archiveofourown.org/users/BladedDarkness/pseuds/BladedDarkness
Summary: <blockquote class="userstuff">
              <p>Your first year is pretty normal, for a witch. It’s only after you get off the train in June that it changes.</p>
<p>General Danvers Week 1, Day 3: Hogwarts.</p>
            </blockquote>





	I'd trade all my tomorrows for just one yesterday

Your first year is pretty normal, for a witch. It’s only after you get off the train in June that it changes.

 

There’s a blonde girl waiting with your parents. They take her home, where you learn that her name is Kara, and that she is the last of a race of magical creatures you had never heard of. Kara isn’t a witch per se, but she’ll be attending Hogwarts with you next year anyways. They don’t tell you where she came from, and honestly you’re not entirely sure they know. You don’t ask either.

 

And absolutely no one can know what Kara really is, which is why she’s been hidden with muggle parents and a muggleborn, Slytherin sister.

 

\-----

 

Second year is weird, and it’s Kara’s fault.

 

Kara, who keeps running through the halls and muttering about a voice only she seems to hear. Sure, Kara’s hearing is better than the average wizard’s, but absolutely no one else can hear the voice and it’s leaving the young Hufflepuff in tears.

 

Then the attacks start. People, animals, even ghosts are found limp, unconscious, with no memory of whatever had assaulted them, and Kara is never too far away, drawn by her strange hearing. There seems to be no signs of any injuries but the disorientation takes weeks to recover from under Madam Pomfrey’s watchful eyes and attentive care.

 

You hear the whispers in the halls and you know Kara must hear them too.

 

“She’s odd, sure, but you don’t really think she’s attacking people, do you?”

 

“You don’t last long without a few tricks if you have a Slytherin sister, mate.”

 

“Her best friend is that Lane girl, too, the snake one.”

 

You’ve always kept mostly to yourself at Hogwarts but Kara attaches herself like a limpet to your  side now, fidgeting with her glasses and shooting wary looks at the Ravenclaw you always share a table with in the library. Vasquez, more reticent than a Slytherin, ignores her.

 

You’re in the Great Hall when a bright green spell hits Kara and she collapses, unresponsive.

 

You fight your way to Kara’s side, your body on autopilot in terror. Headmaster Henshaw puts his hand on your shoulder but you shrug it off, following Madam Pomfrey as floats Kara’s body away.

 

“...Killing Curse,” you hear one of the seventh year Gryffindors mutter, and only your concern for Kara keeps you from bloodying his nose, because he can’t be right.

 

“Here, at Hogwarts?”

 

“Just a first year, too.”

 

All noise filters out when you’re in the Hospital Wing until Headmaster Henshaw is kneeling in front of you.

 

“Alex, she’s going to be okay.”

 

“But. They said it was a K-Killing Curse.” Henshaw shakes his head.

 

“They’re wrong.” His face is serious, eyes focused on you. “Kara isn’t a normal witch, is she?”

 

You remember too late what the older Slytherins said about Legilimency and divert your eyes, but the damage is already done. Henshaw nods. “I thought so. Miss Danvers was hit with a spell that targets her kind. Usually, it is fatal to people like Miss Danvers. It also bears a remarkable resemblance to the Killing Curse, including the fact that there is no physical cause of death. Thankfully, for some reason, this spell was too weak to cause any damage Madam Pomfrey cannot reverse.”

 

“How do I counter it?” This is never going to happen again, you’re sure of it. Nobody is getting a second chance to hurt Kara.

 

“You don’t.”

 

Kara’s magical core is nearly drained completely, and the school sends her home to recover for the rest of the year. It’s only a month, but it feels like an eternity.

 

You’re restless at Hogwarts without Kara, knowing her attacker is still there with you. You take to prowling around, clutching your wand in your sleeve, as if you can goad the person into revealing themselves. Vasquez finds you so often on your wanderings, silently falling into step, you wonder if she has you spelled.

 

Lucy Lane finds you in the Common Room one night, nervously holding a book. “My father kept a journal when he was headmaster.” She holds the book out. “I think I know what happened to Kara.” She flits her eyes back and forth and lowers her voice. “Kara is one of the Kryptonian, isn’t she? He was an Auror during the war, and he talks about how to take them down all the time.”

 

You don’t confirm it, but you take the journal to Headmaster Henshaw. By the end of the school year, Acting Headmaster Lane’s modification to the wards of Hogwarts has been removed.

 

It is not as satisfying as it should be.

 

\-----

 

You’re sitting at the Hufflepuff table at the beginning of third year when Kara emits a squeak at the Daily Prophet. She thrusts the paper at you. “Look at this!”

 

And oh,  _ wow _ .

 

The picture captures your attention first. At fourteen, you’re just realizing how attractive some of your classmates are. Vasquez looks far better sitting on a broom than she has any right to.

 

The woman is the picture of highborn aristocracy, with cold eyes and an eyebrow that arches higher the longer you stare. The photo sniffs, turning its nose up at you, though it seems to soften when Kara presses against you. You look at the headline.

 

**_Breakout from Azkaban! The General Escapes!_ **

 

Kara leans in closer. “Alex,” she whispers. “That’s my aunt.”

 

Your breath hitches in fear. What does this mean for Kara? The General was one of the worst of the Kryptonian, feared throughout all of magical Britain, according to the books you’ve read. No one ever speaks her name.

 

You’re distracted by a commotion at the Ravenclaw table. Lucy’s sister is fighting with her girlfriend again.

 

Kara is devastated when, not two days later, the Head of the Department of Magical Law Enforcement arrives, Kryptonite Curse wardstones in tow. The Quidditch pitch is too close to the border of Hogwarts, and Kara had been hoping to try out for the Hufflepuff Seeker slot.

 

It makes you despise Head Auror Lane all over again.

 

You’re in Hogsmeade with Vasquez when the Ravenclaw curses quietly, folding up a piece of parchment. “What?” 

 

Vasquez pulls you aside, handing you the parchment. You open it, stunned. “It still needs some work, there’s always a bit of magical interference right now,” she says, and a piece of the castle fizzles out briefly. “Your sister is sneaking out through one of the secret passages,” adds Vasquez, tapping on a portion of the map.

 

Your eyes track the three dots, Kara’s in the middle. “Shit,” you groan.

 

“It’s not safe for her, right?”

 

You think your parents underestimated just how hard keeping Kara a secret would be.

 

“We just wanted to see what all the fuss was about,” Kara protests when the two of you corner her in Honeydukes. There’s chocolate around her mouth and you heave a sigh. The Gryffindor behind her squeaks and Lucy elbows him.

 

“You’re just lucky Lane’s wardstones don’t penetrate underground. Now get back to the school,” you say, glaring at Allen for good measure, since he’s the one that led them out in the first place. He winces again and bolts for the back room, dragging Kara and Lucy with him.

 

“How is that boy a Gryffindor again?” Vasquez mutters.

 

“Grant says he probably asked the Hat.”

 

It becomes a habit, checking on Kara. Vasquez gives you a copy of her map, magically linked so that it updates when she makes modifications on her own.

 

Your sister sneaks out far more often than you suspected. You’re not sure if it's the Gryffindor’s or Lane’s fault. Probably both. Usually the three just wander around the castle, but tonight they’re out on the grounds.

 

You spot another name on the map about to intercept them, and you’re shoving the parchment into your pocket and hurrying to find Kara at the far side of the Black Lake.

 

It’s her.

 

Astra In-Ze.

 

Right hand to the Dark Warlord.

 

The General.

 

She looks the same as the picture in the Daily Prophet. Better, even, perhaps, which makes no sense because she’s been in Azkaban all that time and then on the run.

 

She’s also hugging Kara and the expression on her face is undeniably love. They’re muttering in a language Kara has scarcely begun to teach you.

 

It happens in a blur, Head Auror Lane appearing and his men firing Kryptonite Curses, the General covering Kara with her body as the green light passes over them, never touching but weakening all the same. There’s a crack as Allen is shoved aside into Lucy and they both pitch into the mud.

 

You wake up in the Hospital Wing, Kara unconscious in the bed next to you. Headmaster Henshaw straightens from where he was quietly talking with Lucy and makes his way over to you, looking at Allen briefly on your other side.

 

“Miss Lane has explained the situation to me,” he says, and you wish someone would explain it to you. 

 

“Kara?”

 

“Miss Danvers is fine,” soothes the Headmaster. He turns to Allen. “Mr. Allen, we have a limited amount of time.

 

Barry finishes shaking out the leg you heard break earlier and stands, moving to the back of the Hospital Wing. “I’m ready.”

 

Headmaster Henshaw eyes him a moment longer, then grunts. “One hour, old Potions storeroom, Astronomy Tower, Hospital Wing. It’s now 3:04 in the morning. Don’t be late and certainly not early.”

 

Your mouth drops opens as Allen takes a runner’s stance and blurs into a sudden... portal? Seven seconds later, he’s slipping through the entrance of the Hospital Wing. “It’s done,” he says. Henshaw claps his hands together and leaves.

 

“How did you do that?  _ What _ did you do?”

 

Allen fidgets. “Don’t get stung by a Billywig and struck by lightning at the same time. It sucks.”

 

\-----

 

The Yule Ball is boring, something the older Slytherins had told you before but as a fourth year, you’d been eager to go. You and Vasquez amuse yourselves by slipping Fizzing Whizzbees into the punch.

 

The highlight of the night is the two Head Girls getting caught by McGonagall behind the giant cat ice sculpture, charmed to change colors every two minutes. Grant is unrepentant, smirking widely at her fellow Ravenclaw’s flush.

 

Lord - Professor Max, he insists - has always rubbed you the wrong way. He’s a braggart, but somehow a competent one. He’s also managed to avoid the rumored curse on the Defense Against the Dark Arts post for the last three years.

 

So when Kara ends up in the Hospital Wing at the end of the year for the  _ third year in a row _ (you can already hear your mother’s chastisements), after a demonstration in Lord’s class has gone wrong, you’re understandable suspicious.

 

Because Kara needed a Blood Replenishing Potion.

 

But Kara doesn’t bleed. Ever.

 

Which meant Lord had made your sister do so intentionally.

 

You aren’t sad to see him go at the end of the year.

 

\-----

 

You spend the summer between fourth and fifth year with Kara and Barry Allen, at the residence of the once Ancient and Noble House of Ze, per Henshaw’s requests to your parents.

 

There’s a fine layer of dust over almost everything, despite the fact that the General has been living here for over a year. Clearly, her housekeeping skills are lacking.

 

She trains Kara to use the powers that all the Kryptonian have, but also works equally to improve Barry’s aim with his spellcasting, and your speed. You find your wand flying across the room more often than not, until one day you wave your hand angrily after being disarmed and send Allen flying into the wall.

 

The General gives you a warm, impressed look, and she becomes Astra. There’s early morning conversations over hot cups of tea, when Kara and Barry are still lazing about in their beds. Her smiles grow wider and softer, though never the same as the one she gives Kara.

 

She tells you of the mistakes she’s made, how her husband had swayed her natural arrogance into believing that the Kryptonian were superior to both muggles and wizards alike. Astra speaks of rising quickly through the Dark Warlord’s ranks, how her excitement for battle and pride had blinded her to the destruction of her actions, how the Wizarding World turned against the Kryptonian as a species. How Jor-El, Kara’s paternal uncle, devised a prison to contain the Kryptonian who were violent, long before the Kryptonite Curse was created.

 

In return, you tell her about Kara’s years at Hogwarts, how Lane’s wards had tried to pull her in by mimicking voices you know now are ones of her family, before they were wiped out. You tell her about how Kara flies, how she soars and dives and always spots the Snitch before the opposing Seeker (you also grumble about how awful the Slytherin Seeker is) and how brightly Kara smiles when she gets a letter from Astra during breakfast in the Great Hall.

 

Astra teaches you how to physically disarm muggles and wizards alike, how to leverage your strength and weight, and the weak points of the Kryptonian body, few as they are. She gives you a knife that glows the sickly green you hate, and makes you swear to keep it on you at all times, assures you that it cannot harm Kara when sheathed. There’s tea and quiet evenings in the library while Kara and Barry play Exploding Snap in the dining room.

 

The summer ends too quickly, for once.

 

You start adding your own letters to Astra attached to Kara’s every week. They’re often filled with inconsequential things, though you ask her opinions on practically every subject as well. The Kryptonian have always taught their children separate from the Wizarding World, so Astra finds your classes fascinating, particularly Transfiguration (it makes more sense now, why Kara has always struggled with it).

 

It doesn’t last. 

 

Four days before winter break, Professor Crane pulls you from the Common Room just after eleven at night, ushering you to Headmaster Henshaw’s office. McGonagall is there, but Sprout and Crane leave as soon as Kara joins you.

 

Henshaw looks older, as if he has grayed overnight, but you’re not sure if it’s a trick of the light or the weight of what he has to tell you. 

 

“Do either of you know what the Veil is?” he asks, and you shake your head, surprised when Kara pipes up.

 

“It’s the portal to the Phantom Zone. It’s where the worst criminals of the Wizarding World are banished. The Kryptonian had their own Veil, but it was destroyed during the war. General Dru-Zod and most of his followers were sentenced there,” Kara explains. “It’s been unusable since the war, though, because my uncle designed it and it required his blood to open the portal. But Jor-El and my… family, they were killed by wizarding protesters right after he banished Zod.”

 

Henshaw nods. “The Ministry Veil was opened tonight, little more than an hour ago.”

 

Kara stares at him. “That’s not possible,” she asserts as strongly as a fourteen year old can.

 

“Maxwell Lord was found dead at the scene.”

 

“The accident last year,” you realize, and Henshaw grimaces in confirmation.

 

“There’s more,” he adds slowly, and your skin starts to prickle at his reluctance. “I’ve been monitoring the Veil since Miss Danvers was injured. When my wards were tripped this evening, Professor McGonagall and I picked up Astra In-Ze and tried to head off Lord. He was dead by the time we got there and most of the Kryptonian were already through, including Zod.” He wets his lips. “Kara, I’m sorry, but during the skirmish, Astra was shoved through the Veil just before it closed.”

 

Kara pales, shaking. Then her brows seem to furrow and she pulls away from you, standing. “Take me there,” she demands.

 

Henshaw shakes his head. “The Ministry has Aurors all over the room right now. They’re not allowing anyone access right now and likely won’t for some time.” He rubs the bridge of his nose. “And if Lane finds out about you, Kara, well. He has a lot of support in the Ministry, especially now. People are terrified with Zod on the loose again.” His eyes connect with your own. “We have to keep you safe, Kara. You’re the only one capable of opening the Veil now.” You nod.

 

Kara scowls. She’s crying but still furious, and her fists buckle his desk in half. McGonagall shouts an appalled “Miss Danvers!” but Kara is already through the door and you stumble after her because Astra.

 

Astra is gone.

 

Kara pulls you into an alcove, producing an empty vial from somewhere on her person and uncorking it violently; the cork bounces off the stone down the hall. Then she’s opening your robes and reaching underneath them.

 

“Kara!” you hiss at her, but she’s pulling the knife from your hip and slashes it across her palm before you can stop her. She fills the vial and summons the cork, stoppering it as she smoothly slides the knife back its sheathe.

 

“You keep this safe,” she pleads, casting a Stasis Charm on the vial.

 

“Kara, no.” You try to infuse your strength as her big sister into your voice. “You’re not going to Ministry right now, not with Lane and the Dark Warlord on the loose.”

 

“If something happens to me,” starts Kara, and you shake your head, “then you get Aunt Astra out of there as soon as it’s safe, okay?”

 

“Promise me you won’t go, not alone,” you push. Kara looks at you for a moment, then nods.

 

“Not yet,” she agrees.

 

The two of you head home on winter break, though it turns out to be only a quick pitstop as Henshaw relocates the Danvers family. The House of Ze opens for Kara and you can tell it leaves her shaken.

 

\-----

 

Three years later, Kara is seventeen, and you can’t keep her out of the fight anymore. The list of people sheltering at the House of Ze has grown over the years and Kara becomes more frustrated as more of her loved ones are hurt.

 

Astra’s presence still lingers in the house.

 

When the final battle ends at Hogwarts (though you didn’t know it was the last at the time), Barry quickly staggers over carrying Kara, her face tinged a sickly green.

 

Kara, who has been through so much, losing her parents, her people, her aunt, that freaky crossbred plant-parasite Hagrid and Sprout had lost control of, the weight of being the only one capable of sending the renegade Kryptonian back where they belong. Kara, who is pierced through with flecks of Kryptonite-infused crystal, like every other Kryptonian on the battlefield, because Head Auror Lane - still alive, somehow - fires indiscriminately.

 

\-----

 

Kara isn’t with you when you smear her blood on the Veil and Astra stumbles out, immediately weakened by the Kryptonite wardstones set up around the room. What’s left of the Dark Warlord’s forces are shoved through the portal as quickly as possible, and Astra stares at you with wide eyes when Lane tries to get passed you to her.

 

“Alex? Where’s…?” she asks, and you realize she’s not sure because it’s been years for you but only a moment for her and you’re so much older now. You nod, but you can’t quite meet her eyes, because she gave you that knife and training with a purpose and you hadn’t succeeded.

 

“She’s,” your voice cracks, and you take her hand. “She’s in St. Mungo’s.”

 

You remembered Barry’s words when you had asked, how he had shook his head, and though you’d like nothing better than to take Astra back to when Kara was fourteen, and to go back yourself, you know nothing good would come of it.

 

Astra’s hand tightens around your own, and your stomach swoops uncomfortably again.

**Author's Note:**

> I had to fight with this every step of the way, for a number of reasons, the first being that it insisted on being written in second person.
> 
> I consider this a pre-relationship fic, because this is a universe I'd like to play in some more, though I have no clue when. Think of this fic as the backbone of that universe, with hints of the full expansion.
> 
> If you haven't noticed yet, I focus a lot on Astra's and Alex's bonds with Kara in my fics about them, and there's a lot of backstory to get through before even getting to Astra and Alex together.
> 
> Because there's a lot that I only hinted at in this, please ask me if you want to know more about something. I will type your ear off about it, especially if you're asking for certain choices or if there's confusion about something I barely touched on since it was Alex's POV.


End file.
